A Rare Cause Of Facial Paralysis: Moebius Syndrome

Moebius syndrome is a rare, non-progressive congenital syndrome presenting with complete or partial facial paralysis. It is usually associated with orofacial malformations, musculoskeletal defects, brainstem dysplasia, and other cranial nerve palsies. Mean incidence is 2-20/million, although there is considerable regional variation. The most common presentation is with bilateral lateral rectus palsies and facial diplegia. Frequently, the 5th, 10th, 11th and 12th cranial nerves are involved and may cause cough, difficulty in chewing and swallowing, and respiratory insufficiency. Complete or partial facial nerve palsy is necessary for a diagnosis of Moebius syndrome. A 4-month-old girl was brought to our clinic with complaints of inability to close her right eye completely and internal deviation in that eye, beginning from birth. She had micrognathia and an inability to completely close the right eye. Both eyes were turned inwards during primary gaze. She had limited lateral gaze, a pes equinovarus deformity in her feet, and flap ears. Cranial magnetic resonance imaging was performed because of the dysmorphic features and revealed micrognathia and volume loss at the tongue. Bilateral facial nerves could not be visualised by a 3D FIESTA scan, suggesting bilateral facial nerve agenesis. This case is presented to highlight Moebius syndrome in the differential diagnosis of cases presenting with congenital facial weakness.